It is well known in the art to use a fin located on the bottom of a water ski to help stabilize the ski, especially in turns. Since individual needs vary, it is desirable to have an easily adjustable fin to overcome differences in speed, water conditions, and course requirements. Present fin systems do not allow for the precise movement of a fin in relation to the water ski. It is beneficial to be able to make small adjustments for fine tuning the fin's position to a skier's preference and have the fin remain attached to the ski and firmly lock the fin in place after adjustment. Present systems employ a friction system using bolts to squeeze the fin block toward the fin. In order to adjust the fin's position, the bolts must be loosened, hence the fin can come completely out of the fin block. Present fins may have indicia on the side thereof in order to help with adjustments, but are difficult to see and must be used with the curved edge of the slot in the water ski where the fin protrudes through the bottom of the ski.